Positioning based on calendar information

ABSTRACT

A method includes obtaining piece(s) of calendar information indicative of at least one appointment taking place in a space and extracting a set of space identifiers representing space(s) of the venue. The space identifier(s) for one or more spaces are extracted based on an indoor map of the venue. The method also includes determining or triggering determining whether at least a part of the set of space identifiers or one or more spaces of the set of space identifiers match(es) the at least one space as represented by the piece(s) of calendar information; and if a match is found: determining one or more reference location estimates. A respective reference location estimate is indicative of a location of the space that was determined to be a match. A corresponding apparatus, computer program product and system are also provided.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority to European Application No. 19187826.3,filed Jul. 23, 2019, the entire contents of which are incorporatedherein by reference.

FIELD

The following disclosure relates to the field of indoor positioning, ormore particularly relates to systems, apparatuses, and methods fordetermining more accurate location estimates indicative of indoorlocations of mobile devices.

BACKGROUND

Modern global cellular (GSM (Global System for Mobile Communications),CDMA (Code Division Multiple Access), WDCMA (Wideband CDMA), TD-SCDMA(Time Division Synchronous CDMA), LTE (Longterm Evolution), LTE-A (LTEAdvanced), NB-IoT (NarrowBand-Internet-of-Things)) and non-cellular(primarily WLAN (Wireless Local Area Network), but also BT (Bluetooth),BLE (Bluetooth Low Energy), ZigBee, LoRa, to name but a few non-limitingexamples) positioning technologies are based on collecting large globaldatabases containing information on the cellular and non-cellularsignals. A large portion of the data typically originates from the usersof these positioning technologies.

The data from the users is typically in the form of fingerprintsrespectively fingerprint information. Such fingerprints contain GNSS(Global Navigation Satellite System)-based or WLAN-based positionestimate and measurements taken from the radio interfaces (cellular,non-cellular).

The measurements contain e.g.:

-   -   Global and/or Local IDs of the cellular network cells observed,        and, optionally,        -   signal strength and/or pathloss estimates;        -   timing measurements (Timing Advance or Round-Trip Time).    -   BSSIDs (Basic Service Set Identifiers) (MAC (Medium Access        Control) address of the air interface) of the WLAN access points        observed and, optionally,        -   SSIDs (Service Set Identifiers);    -   signal strengths (RSSI (received signal strength index),        physical Rx level in dBm ref 1 mW, etc.)

timing measurements (Round-trip Time).

This data gets uploaded to the server or server cloud, where generatingof models of wireless communication nodes for positioning purposes basedon the fingerprints received from the multitude of the users takesplace. Such models may be coverage areas, node positions, radiopropagation models, Rx fields, etc. In the end, these models aretransferred back to the user terminals for use in positiondetermination.

Although the end user terminal has GNSS-capability, the end user canstill benefit from using cellular/non-cellular positioning technologiesin terms of time-to-first-fix and power consumption. Also, not allapplications require highly accurate GNSS-based position (e.g. for localweather application it suffices to use cell-based location estimate).Also, cellular/non-cellular positioning technologies work indoors and inurban canyons, which are generally challenging environments forGNSS-based technologies.

The positioning can function in two modes. The first mode is theterminal-assisted mode, in which the terminal performs the measurementsof the cellular and/or non-cellular air interface, provides themeasurements to a remote server, which in turn provides the positionestimate back to the device.

The second mode is the terminal-based mode, in which the device has alocal copy of the radio map (or most likely, a subset of the globalradio map). Such a subset can be downloaded by the device from a remoteserver for the (geographic) area of interest (e.g. a small area aroundthe current location, or for a whole country, to name but a fewnon-limiting examples) out of a global radio map comprising a pluralityof such subsets. Such a subset can further be pre-installed to thedevice in the factory, but even in that case the data needs to berefreshed at some point.

Many different approaches were proposed in the prior art for resolvinglocation indoors. Most common ones rely on fusion of GNSS and sensordata and extend location estimation to GNSS-denied areas based on thesensor data. Other approaches rely on probes collected outdoors, inorder to localize probes indoors.

SUMMARY OF SOME EXEMPLARY EMBODIMENTS

However, it is a drawback that while reference locations for probe datacan be easily obtained outdoors, e.g. from GNSS, obtaining referencesindoors is still a big challenge. Because GNSS does not work indoors ingeneral, sensor based solutions quickly diverge in the absence of GNSSfixes. Therefore, any additional source of information from indoors isof great use.

It is thus, inter alia, an object of the invention to achieve a moreaccurate positioning for indoor positioning.

According to a first exemplary aspect of the present invention, a methodis disclosed, the method comprising:

-   -   obtaining one or more pieces of calendar information indicative        of at least one appointment taking place in a space;    -   extracting a set of space identifiers representing one or more        spaces of the venue, wherein the one or more spaces respectively        their one or more space identifiers are extracted based on an        indoor map of the venue;    -   determining or triggering determining whether at least a part of        the set of space identifiers or one or more spaces of the set of        space identifiers matches or match the at least one space as        represented by the obtained one or more pieces of calendar        information; and in case such a match is found:    -   determining one or more reference location estimates, wherein a        respective reference location estimate of the one or more        reference location estimates is indicative of a location of the        space that was determined to be a match, wherein the location of        the space is derived from the indoor map.

This method may for instance be performed and/or controlled by anapparatus, for instance a server. Alternatively, this method may beperformed and/or controlled by more than one apparatus, for instance aserver cloud comprising at least two servers. Alternatively, the methodmay for instance be performed and/or controlled by a mobile device, e.g.a smartphone, tablet, portable navigation device, wearable, IoT(Internet-of-Things) device, to name but a few non-limiting examples.For instance, the method may be performed and/or controlled by using atleast one processor of the server, server cloud, or mobile device.

Such a mobile device may for instance be portable (e.g. weigh less than5, 4, 3, 2, or 1 kg). The mobile device may for instance comprise or beconnectable to a display for displaying information, e.g. a route thatis guided/navigated to a user, to name but one non-limiting example. Themobile device may for instance comprise or be connectable to means foroutputting sound, e.g. in the form of spoken commands or information.The mobile device may for instance comprise or be connectable to one ormore sensors for determining the devices position, such as for instancea GNSS receiver, in the form of a GPS receiver. The mobile device mayfor instance comprise or be connectable to one or more sensors, e.g. inthe form of an accelerometer and/or a gyroscope for gathering (e.g.measuring) further information. The mobile device may for instancecomprise or be connectable to a receiver and/or a transmitter (e.g. atransceiver) for receiving and/or sending information. For instance, themobile device may comprise one or more radio receivers (e.g. radiotransceivers) to gather measurements based on GNSS- or non-GNSS-basedpositioning signals, which may for instance enable a coarse positionestimate indicative of the devices position to be determined ortriggered to be determined. The mobile device may for instance besuitable for outdoor and/or indoor navigation respectively positioning.The mobile device may for instance comprise various other componentslike a user interface for receiving user input.

According to a further exemplary aspect of the invention, a computerprogram is disclosed, the computer program when executed by a processorcausing an apparatus, for instance a server, to perform and/or controlthe actions of the method according to the first exemplary aspect.

The computer program may be stored on computer-readable storage medium,in particular a tangible and/or non-transitory medium. The computerreadable storage medium could for example be a disk or a memory or thelike. The computer program could be stored in the computer readablestorage medium in the form of instructions encoding thecomputer-readable storage medium. The computer readable storage mediummay be intended for taking part in the operation of a device, like aninternal or external memory, for instance a Read-Only Memory (ROM) orhard disk of a computer, or be intended for distribution of the program,like an optical disc.

According to a further exemplary aspect of the invention, an apparatusis disclosed, configured to perform and/or control or comprisingrespective means for performing and/or controlling the method accordingto the first exemplary aspect.

The means of the apparatus can be implemented in hardware and/orsoftware. They may comprise for instance at least one processor forexecuting computer program code for performing the required functions,at least one memory storing the program code, or both. Alternatively,they could comprise for instance circuitry that is designed to implementthe required functions, for instance implemented in a chipset or a chip,like an integrated circuit. In general, the means may comprise forinstance one or more processing means or processors.

According to a further exemplary aspect of the invention, an apparatusis disclosed, comprising at least one processor and at least one memoryincluding computer program code, the at least one memory and thecomputer program code configured to, with the at least one processor,cause an apparatus, for instance the apparatus, at least to performand/or to control the method according to the first exemplary aspect.

The above-disclosed apparatus according to any aspect of the inventionmay be a module or a component for a device, for example a chip.Alternatively, the disclosed apparatus according to any aspect of theinvention may be a device, for instance a server or server cloud. Thedisclosed apparatus according to any aspect of the invention maycomprise only the disclosed components, for instance means, processor,memory, or may further comprise one or more additional components.

The apparatus may for instance be a server, a server cloud or a mobiledevice, or a module of a server, a server cloud, or a mobile device, ora component (e.g. a chip) of a server, a server cloud, or a mobiledevice.

According to a further exemplary aspect of the invention, a system isdisclosed, comprising:

an apparatus (e.g. a server or a server cloud) according to any aspectof the invention as disclosed above, and one or more mobile devices,wherein the one or more mobile devices are respectively configured toprovide one or more pieces of calendar information, and optionally, oneor more pieces of fingerprint information to the apparatus.

According to a further exemplary aspect of the invention, a system isdisclosed, comprising: a plurality of apparatuses (e.g. at least two)according to any aspect of the invention as disclosed above.

In the following, exemplary features and exemplary embodiments of allaspects of the present invention will be described in further detail.

Each respective piece of the one or more pieces of calendar informationmay for instance be indicative of at least one appointment.Alternatively, some piece(s) of the one or more pieces of calendarinformation may for instance not be indicative of any appointment.Further, all of the pieces of the one or more pieces of calendarinformation together may for instance be indicative of at least oneappointment

The one or more pieces of calendar information may for instance beobtained by retrieving the one or more pieces of calendar information incase of a respective mobile device performing and/or controlling themethod according to the first exemplary aspect of the present invention.The one or more pieces of calendar information may for instance beobtained by receiving the one or more pieces of calendar information incase of a respective server or server cloud performing and/orcontrolling the method according to the first exemplary aspect of thepresent invention.

A venue may for instance be a building, shopping mall, office complex,public accessible location (e.g. station, airport, university or thelike), to name but a few non-limiting examples. An area may for instancebe a public place, urban area, rural area, industrial area, or acombination thereof, to name but a few non-limiting examples. The spacemay for instance be a specific room, area, and/or part of an area and/orvenue. Thus, such a space is located within an area and/or venue.

Each respective piece of the one or more pieces of calendar information,or at least a part of the one or more pieces of calendar information mayfor instance further be indicative of a specific area and/or venue, butit may for instance also be possible that the respective area and/orvenue is unknown, thus, not being comprised or represented by arespective piece of calendar information, or at least a part of the oneor more pieces of calendar information. In the latter case, only one ormore specific spaces (e.g. represented by one or more space identifiers,e.g. space names, to name but one non-limiting example) may for instancebe known. A respective piece of calendar information, or a part of it,may at a minimum be indicative of a respective space identifier the atleast one appointment should take or takes place within the area and/orvenue.

One or more radio nodes may for instance be comprised by an area and/ora venue, e.g. by an infrastructure of the venue and/or area, or a partof it. Such a radio node of the one or more radio nodes may for instancebe a radio node, e.g. of the area and/or venue. Such a radio node mayfor instance be used for indoor positioning and/or floor detection, e.g.according to BT- (Bluetooth) and/or BLE- (Bluetooth Low Energy)specification, or may for instance be a Wi-Fi Access Point for indoorpositioning and/or floor detection, e.g. according to the WLAN-(Wireless Local Area Network) specification, to name but a fewnon-limiting examples.

Such a radio node (e.g. WiFi access point, beacon device, or acombination thereof, to name but a few non-limiting examples) of the oneor more radio nodes, e.g. of the area and/or venue, may for instancecomprise or be connectable to a transceiver, e.g. according to the BT-,BLE, and/or WLAN-specification to provide wireless-based communication.Each radio node of the one or more radio nodes, e.g. of the area and/orvenue, may for instance use such a transceiver for transmitting and/orbroadcasting one or more signals, e.g. comprising one or moreinformation (e.g. one or more identifiers), such as a SSID of therespective radio node of the one or more radio nodes.

Signals sent by such one or more radio nodes may for instance begathered (e.g. measured) as one or more pieces of fingerprintinformation. Such one or more pieces of fingerprint information may forinstance be gathered (e.g. measured) by one or more mobile devices. Arespective fingerprint information of the one or more pieces offingerprint information may for instance be indicative of one or moreobservation reports of signals sent by one or more radio nodesobservable at a certain location. For example, the radio transmissionparameters of a parametric radio model of a radio positioning supportdevice may at least partially correspond to and/or be determined basedon one or more radio transmission parameters associated with this radionode of the one or more radio nodes, wherein the one or more radiotransmission parameters associated with this radio node of the one ormore radio nodes may for example be represented by and/or contained inthe one or more observation reports (e.g. one or more observationreports associated with the radio node and/or an (e.g. adjacent) radionode of the one or more radio nodes), e.g. in the form of one or morepieces of fingerprint information.

A respective fingerprint information of the one or more pieces offingerprint information may for instance at least be indicative of oneor more identifiers of one or more radio nodes which respective signalsare observable at a certain location at which the respective fingerprintinformation is gathered. For instance, based on such one or moreidentifiers of the one or more radio nodes, a respective location of arespective radio node may for instance be determined, e.g. based on alook-up table to name but one non-limiting example.

Further, based on a respective fingerprint information a location mayfor instance be determined at least partially based on an indoor radiomap of an area and/or venue (e.g. the area and/or venue) since it mayfor instance be derivable from such an indoor radio map at whichspecific location a certain selection of one or more radio nodes of thearea and/or venue are observable. It will be understood that forinstance in case a respective fingerprint information is furtherindicative of one or more radio transmission parameters, as disclosedabove, the respective location may for instance be determined (e.g.estimated) more accurately.

According to an exemplary embodiment of all exemplary aspects of thepresent invention, the method further comprises:

-   -   determining or triggering determining one or more coarse        location estimates.

A respective coarse location estimate of the one or more coarse locationestimates may for instance be indicative of or represent an estimationof a location at which a device (e.g. a mobile device) whose location isto be determined is located. The coarse location estimate may forinstance comprise or represent a pair of coordinates, e.g. latitude- andlongitude coordinates or x-, and y-coordinates. Alternatively, thecoarse location estimate may for instance comprise or representthree-dimensional coordinates, e.g. latitude-, longitude- andaltitude-coordinates, or x-, y- and z-coordinates.

The one or more coarse location estimates may for instance represent oneor more locations of the respective mobile device(s) at which they arelocated e.g. in the area and/or venue during the time of appointment,e.g. represented by the variables or parameters [XTimeA1, XTimeA2, . . .]. The one or more coarse location estimates may for instance bedetermined at least partially based on GNSS/Wi-Fi/cellular signals, e.g.comprised or represented by a respective fingerprint information of oneor more pieces of fingerprint information. It is noted that thisexemplary step may for instance only facilitate a further search for oneor more space identifiers to be comprised by the set of spaceidentifiers, but is not strictly necessary, it is also possible that oneor more locations of the respective one or more spaces of the areaand/or venue already exist in the one or more pieces of calendarinformation, e.g. as details of the at least one appointment.

One or more coarse location estimates may for instance be determined ortriggered to be determined. For instance, a respective coarse locationestimate may for instance be triggered to be determined by a respectivemobile device, wherein e.g. a fingerprint information may for instancebe sent and then be obtained by a respective server so that therespective server is enabled to determine (e.g. estimate) the respectivecoarse location estimate. In this case, the respective coarse locationestimate(s) may for instance be determined by a server or a servercloud, e.g. a positioning server, e.g. based on a request that isreceived. Thus, e.g. the server or the server cloud is triggered todetermine the coarse location estimate.

Additionally or alternatively, a respective coarse location, or the oneor more coarse location estimates may for instance be determined, e.g.by the at least one apparatus performing and/or controlling the methodaccording to the first exemplary aspect of the present invention.

A respective coarse location estimate may for instance be determined ortriggered to be determined based on GNSS (Global Navigation SatelliteSystem)-based and/or non-GNSS-based positioning. Examples for GNSS-basedpositioning are GPS, GALILEO, GLONASS (Globalnaja nawigazionnajasputnikowaja sistema), and examples for non-GNSS-based positioning arefingerprinting based on radio signals sent by e.g. BT/BLE beacons and/orWLAN access points, to name but a few non-limiting examples.

A respective coarse location estimate indicative of a location of arespective mobile device (e.g. within the area and/or venue) may forexample indicate a pre-determined area and/or space covering the (e.g.absolute) position of the respective mobile device, but may not indicatethe specific, thus more accurate, (e.g. absolute) position of therespective mobile device. For example, the pre-determined area and/orspace may be part of a plurality of pre-determined areas and/or spacesfor each of which it is pre-determined whether or not it is part of thevicinity of the pre-determined area and/or venue, to name but onenon-limiting example. A GNSS-based and/or the a-GNSS (assistedGNSS)-based positioning may for instance use one or more pieces offingerprint information (e.g. observation report(s)) of measured (e.g.radio) signals or radio signal parameters to be considered. Each ofthose measurements may for instance be considered to be indicative ofwhether or not the respective mobile device was located in the vicinityof the pre-determined area and/or venue when the respective radiosignals and/or radio signal parameters were gathered (e.g. measured orcaptured). For example, the respective mobile device may be consideredto be in the vicinity of the pre-determined area and/or venue, if therespective radio signals and/or radio signal parameters represented bythe one or more measurements indicate a pre-determined area at leastpartially defining the vicinity of the pre-determined area and/or venue.

A set of (e.g. potential) space identifiers (e.g. names of respectiveone or more spaces located within the area and/or venue) representingone or more spaces of the area and/or venue are extracted. Further, theone or more spaces respectively their one or more space identifiers mayfor instance be extracted based on (e.g. out of) an indoor map. Therespective indoor map may for instance be obtained (e.g. retrieved froma memory) or received prior to the extracting of the set of spaceidentifiers of the area and/or venue. Such an indoor map may forinstance be a floor plan of the area and/or venue, which may forinstance at least comprise one or more space identifiers (e.g. names ofspaces and/or locations) within the area and/or venue. Such an indoormap of a respective area and/or venue may for instance be obtainablefrom a public accessible database, e.g. via the Internet, to name butone non-limiting example. The indoor map may for instance be associatedwith respectively linked to the area and/or venue a respective mobiledevice is currently located. This may for instance be determined basedon at least one respective coarse location estimate of the one or morecoarse location estimates, to name but one non-limiting example.

The extracting of the one or more space identifiers to be comprised bythe set of space identifiers out of the indoor map of the respectivearea and/or venue may for instance be performed and/or controlled atleast partially automatically and/or repeatedly (e.g. periodicallyand/or continuously and/or for a pre-determined period of time). In thisway, the set of space identifiers of a certain area and/or venue may forinstance be updated or expanded by more accurate (e.g. up-to-date)spaces being comprised by the certain area and/or venue. For instance, aset of space identifiers (e.g. space names) in the form {SName1, SName2,. . . } and, optionally, their respective locations in the form{SLocation1, SLocation2, . . . } may for instance be extracted from oneor more indoor maps of the respective area and/or venue. Further, thespace identifiers to be comprised by the set of space identifiers mayfor instance be selected in the vicinity of the respective coarselocation(s) of the mobile device(s), e.g. as represented by thedetermined one or more coarse location estimates.

The extracted space identifiers (e.g. space names), e.g. as {SName1,SName2, . . . } and comprised by the set of space identifiers may forinstance be compared against the SNameA of the space of the at least oneappointment as represented by a respective calendar information of theone or more pieces of calendar information, or as represented by all ofthe one or more pieces of calendar information together.

For instance, if one of the extracted space identifiers SNamei of theset of space identifiers matches with the space identifier SNameA e.g.of a respective calendar information, it can be considered that arespective user of the respective mobile device from which therespective calendar information was obtained, is at the location of thespace associated with the matching name (e.g. derived from an indoormap, as disclosed above). Such a location may for instance berepresented by numerical information (e.g. Latitude, Longitude,floor-coordinates) about the user location.

Further, it is determined or triggered to be determined (e.g. arespective mobile device may for instance request a server to performand/or control the determining) whether at least a part of the set ofspace identifiers or one or more spaces of the set of space identifiersmatches (and/or equals), at least in part, the at least one space (e.g.represented by a respective space identifier) as represented by theobtained one or more pieces of calendar information.

For instance, the set of space identifiers may be in a form of a list.The set of space identifiers (e.g. associated with a certain area and/orvenue) may for instance be stored in a memory, e.g. a database. Further,a stored set of space identifiers may for instance be obtained (e.g.retrieved) from such a database.

For instance, the determining of the match may be performed and/orcontrolled e.g. by comparing space identifier(s) (e.g. names of spacesof the area and/or venue) as comprised or represented by the set ofspace identifiers with respective space identifier(s) (e.g. spacename(s) of the at least one appointment) as represented or derived fromthe one or more pieces of calendar information. A result of such acomparison may for instance be a list of probabilities that a respectivespace identifier of the set of space identifiers represents a respectivespace as represented by the one or more pieces of calendar information,e.g. by a respective space identifier. For instance, a respective pieceof calendar information, or more than one piece of calendar informationmay for instance represent that the at least one appointment is to takeplace in a certain space (e.g. represented by a name of the space) of acertain area and/or venue.

A respective space identifier as comprised by the set of spaceidentifiers, and/or as represented by the one or more pieces of calendarinformation may for instance be a (e.g. character) string. Such a stringof the set of space identifiers may for instance be compared to anotherstring as represented by the one or more pieces of calendar information.Optionally, it may for instance be determined a probability of thecomparison, e.g. only a part of compared strings match with each other.For instance, in case the matching part is sufficiently long (e.g. morethan 3 characters, to name but one non-limiting example) and furtheroptionally, unique, then the probability can be determined to be equalto 1. If, however, the compared space identifiers do not match (e.g. atall), and optionally are not sufficiently long, and further optionally,are not unique, then the probability can be determined to be equal to 0.It will be understood that there may also be one or more intermediatecases between the two aforementioned cases with a probability of 1 andanother probability of 0. For instance, such an intermediate case may bewhen one short variant of the other is determined during the comparison,e.g. “Meeting room” and “M room”, in which case the probability may bebetween 0 and 1, not equaling 0 or 1.

Then, e.g. a certain threshold value may for instance be pre-defined, todetermine whether or not a match is found. For instance, in case aprobability is equal to or above 0.6 (to name but one non-limitingexample) it may for instance be pre-defined that then a match is found.

One or more reference location estimates are determined. A respectivereference location estimate of the one or more reference locationestimates is indicative of a location of the space that was determinedto be a match, wherein the location of the space is derived from theindoor map. The location may for instance be defined by the respectiveindoor map of the venue. For instance, in case a respective coarselocation estimate is indicative of a location roughly in the vicinity ofa certain space of the area and/or venue, based on the respective one ormore pieces of calendar information, a respective reference locationestimate is then determined to be indicative of (or comprise and/orrepresent) the (e.g. exact) location of the space.

The one or more reference location estimates may for instance be stored,e.g. in a memory. Such a memory may for instance comprise a database.The memory may for instance be comprised by or be connectable to theapparatus performing and/or controlling the method according to thefirst exemplary aspect of the present invention. Then, the one or morereference location estimates may for instance be used e.g. in thefuture, e.g. for comparing the coarse position estimate with the one ormore reference location estimates. For instance, the one or morereference location estimates can then be used to determine more accuratelocation estimates in a positioning. Further, the one or more referencelocation estimates stored in the memory may for instance be associatedwith (e.g. linked to) a respective mobile device, e.g. via an identifierof the respective mobile device. In this way, the one or more referencelocation estimates may for instance be kept (e.g. stored) in apersonalized way, e.g. to use a respective reference location estimateonly for a respective mobile device. In this way, efficiency of apositioning that is at least partially be based on such one or morereference location estimates is enhanced.

Further, the one or more reference location estimates may for instancebe provided (e.g. sent or output), e.g. to an entity from which e.g. arespective calendar information of the one or more pieces of calendarinformation stems. Alternatively, the one or more reference locationestimates may for instance be provided to another entity that isdifferent from the entity e.g. from which a respective obtained calendarinformation stems, and which transmits (e.g. relays) the one or morereference location estimates to the entity from which the respectiveobtained calendar information of the one or more pieces of calendarinformation stems. The one or more reference location estimates may forinstance be output via a communication interface of the apparatusperforming and/or controlling the method according to the firstexemplary aspect of the present invention. Such a communicationinterface may for instance comprise one or more radio transceiver (e.g.transmitter and receiver), e.g. according to WLAN, BT, BLE, cellular, ora combination thereof communication standard, to name but a fewnon-limiting examples.

According to an exemplary embodiment of all exemplary aspects of thepresent invention, the method further comprises:

-   -   storing and/or providing the determined one or more reference        location estimates to be utilized as reference for further        sensor data.

The one or more determined reference location estimates may for instancebe stored in a memory, e.g. comprised by or connectable to the apparatusperforming and/or controlling the method according to the firstexemplary aspect of the present invention.

The one or more determined reference location estimates may for instancebe provided, e.g. to one or more further entities, and/or to one or moremobile devices. The one or more determined reference location estimatesmay for instance be provided by sending the one or more determinedreference location estimates, e.g. directly to one or more entities(e.g. one or more mobile device in case the apparatus is a server orserver cloud) that are different from the apparatus performing and/orcontrolling the method according to the first exemplary aspect of thepresent invention, or to another entity that may for instance relay theone or more determined reference location estimates to one or moreentities.

According to an exemplary embodiment of all exemplary aspects of thepresent invention, the calendar information is further indicative of atime period of the at least one appointment.

The time period of the at least one appointment may for instance definea time for the start of the at least one appointment. Further, the timeperiod may for instance define a time for the end of the at least oneappointment. The time period may be defined with some sort of tolerancedt, e.g. to account for a user coming early or late to the at least oneappointment (e.g. a meeting) or leaving the at least one appointmentmeeting early or late, to name but a few non-limiting examples.

For instance, the at least one appointment may be represented by arespective calendar information of the one or more pieces of calendarinformation by a name of the at least one appointment. For instance, theat least one appointment may for instance take place in a certain spaceof the area and/or venue. Such a space may for instance be representedby the variable or parameter SNameA. Thus, a respective calendarinformation of the one or more pieces of calendar information may forinstance comprise or represent the variable or parameter SNameA. Thespace identifier of the at least one appointment may for instance beextractable from a respective calendar information, and/or the one ormore pieces of calendar information.

For instance, at the time (e.g. start of a meeting) of the at least oneappointment, a respective coarse location estimate of the one or morecoarse location estimates may for instance be determined. Further, oneor more coarse location estimates for one or more mobile device (e.g. aplurality of mobile device) may for instance be determined. Forinstance, one respective coarse location estimate for every userattending the at least one appointment may for instance be determined.

For instance, from the one or more pieces of calendar information,information of at least one appointment of a user of the respectivemobile device from which at least one piece of calendar information ofthe one or more pieces of calendar information stems may for instance beobtained (e.g. extracted), e.g. including or comprising one or more ofthe following:

-   -   a time period of the at least one appointment, e.g. represented        by the variables or parameters [TimeAstart, TimeAend]; and    -   Name of the at least one appointment space, e.g. represented by        the variable or parameter SNameA (e.g. a meeting room name),    -   wherein A refers to a specific appointment.

The estimated location of the respective mobile device during the atleast one appointment may for instance be used to reference devicesensor data, such as Wi-Fi/BLE/cellular measurements. For this purpose,according to an example embodiment of all exemplary aspects of thepresent invention, one or more pieces of reference location estimatesare determined. Such one or more pieces of reference location estimatesmay for instance comprise geo-referenced radio measurements (e.g. in theform of one or more pieces of fingerprint information, to name but onenon-limiting example). They may for instance then be used for an indoorradio map generation. Such an indoor radio map can then be used forindoor positioning, to name but one non-limiting example.

Further, e.g. to account for a user to attend to the at least oneappointment later or leaving earlier from the at least one appointment,the time period [TimeAstart+dt, TimeAend−dt] may for instance beconsidered. Additionally, sensor data of the respective mobile device ofthe user may for instance be used, e.g. to estimate a time when user isfinally in the at least one appointment. This may for instance be doneby considering only a respective time period when the user of therespective mobile device does not move significantly or does not makesteps, e.g. according to information gathered by an acceleration sensorof the respective mobile device, to name but one non-limiting example.

In this way, example embodiments according to all aspects of the presentinvention provide a way to learn e.g. geo-referenced radio measurements(as represented by the one or more pieces of reference locationestimates) from indoors respectively indoor positioning scenarios, wheretraditional positioning methods fail.

According to an exemplary embodiment of all exemplary aspects of thepresent invention, the calendar information is associated with a user ofa mobile device.

A respective calendar information of the one or more pieces of calendarinformation may for instance further be indicative of a user identifierenabling to identify a respective user or a respective mobile devicefrom which a respective calendar information of the one or more piecesof calendar information stems (e.g. was received). Such a useridentifier may for instance be a MSISDN (Mobile Station IntegratedServices Digital Network Number), a MAC (Medium Access Control) addressof a respective mobile device, or any kind of identification enabling arespective mobile device to be identified, to name but a fewnon-limiting examples.

According to an exemplary embodiment of all exemplary aspects of thepresent invention, the space of the venue is represented by a characterstring.

Such a character string may for instance be comprised by a respectivespace identifier. For instance, in case the one or more spaceidentifiers of the set of space identifiers are determined based on anindoor map of the area and/or venue, a respective character stringenabling identifying a space in the area and/or venue may for instancebe comprised in the respective indoor map of the area and/or venue.

Then, e.g. one or more string-matching methods may for instance be usedto determine the match between one or more space identifiers of the setof space identifiers, and one or more further space identifiers e.g. asextracted or derived from the one or more pieces of calendarinformation.

According to an exemplary embodiment of all exemplary aspects of thepresent invention, the determining of the one or more coarse locationestimates further comprises:

-   -   obtaining or gathering one or more pieces of fingerprint        information, wherein the obtaining or the gathering is performed        and/or controlled during the time period of the at least one        appointment; and    -   wherein the one or more coarse location estimates are determined        at least partially based on the one or more pieces of        fingerprint information, wherein optionally the one or more        coarse location estimates are determined or triggered to be        determined during the time period of the at least one        appointment.

The one or more pieces of fingerprint information are obtained in casethe apparatus performing and/or controlling the method according to thefirst exemplary aspect of the present invention is a server or servercloud. In case the apparatus performing and/or controlling the methodaccording to the first exemplary aspect of the present invention is amobile device, the mobile device may for instance gather the one or morepieces of fingerprint information.

A respective fingerprint information of the one or more pieces offingerprint information may for instance be indicative of at least oneidentifier of at least one radio node which sent signals are observableat the location at which the respective fingerprint information isgathered (e.g. measured). Further, a respective fingerprint informationof the one or more pieces of fingerprint information may for instance beindicative of at least one received signal strength value with whichsent signals are observable at the location at which the respectivefingerprint information is gathered (e.g. measured). A respectivefingerprint information may for instance enable a location to bedetermined at least partially based on a (e.g. indoor) radio map (e.g.of an area and/or venue) and the respective fingerprint information. Forinstance, based on knowing from which one or more radio nodes, andoptionally, with which received signal strength value signals from theone or more radio nodes located in an area and/or venue (e.g. the areaand/or venue) are observable, a location can be determined by comparingthe respective fingerprint information to respective information ascomprised or represented by a respective (e.g. indoor) radio map. Thedetermining of the location may for instance be performed and/orcontrolled by a respective mobile device which gathered the respectivefingerprint information, or may for instance be triggered to bedetermined e.g. from a positioning server providing such a determiningof a location as a service.

The apparatus performing and/or controlling the method according to thefirst exemplary aspect of the present invention may for instance obtain(e.g. collect) and store sensor data (e.g. in the form of fingerprintinformation) from the user respectively their mobile device(s) duringthe time period [TimeAstart, TimeAend] of the at least one appointment,particularly based on Wi-Fi and BLE signal measurements.

Further, a respective fingerprint information may for instance beindicative of information gathered (e.g. measured) by one or moresensors comprised by or connectable to the respective mobile device,such as a gyroscope, an accelerometer, an inertial sensor, barometricsensor, e.g. to gather (e.g. measure) respective information e.g.indicative of a position and/or orientation and/or velocity of therespective mobile device in its surrounding, and/or an (e.g. absolute orrelative) altitude value of the respective mobile device, to name but afew non-limiting examples.

According to an exemplary embodiment of all exemplary aspects of thepresent invention, the set of space identifiers is extracted furtherbased on the one or more coarse location estimates, wherein the set ofspace identifiers comprises one or more spaces located in the vicinity(e.g. circle of pre-defined radius) of the one or more coarse locationestimates.

The extracting of the set of space identifiers may for instance furthercomprise:

-   -   obtaining one or more space identifiers of one or more spaces.

For instance, the one or more spaces may be in the form of a list{Space1, Space2, . . . }, wherein the one or more spaces are located inthe vicinity of the locations as represented by the coarse locationestimates, e.g. obtained or gathered at the time period the at least oneappointment takes place, e.g. in the following form: [XTimeA1, XTimeA2,. . . XTimeAK]. Such a list may for instance comprise the one or morespace identifiers (e.g. space names) {SName1, SName2, . . . } andfurther the one or more space locations {SLocation1, SLocation2, . . .}. Such a list may for instance be obtained from an indoor map of thearea and/or venue. Further, a circle of a pre-defined radius aroundmedian of locations [XTimeA1, XTimeA2, . . . , XTimeAK] may for instancebe considered as an area of proximity to extract the set of spaceidentifiers.

The extracting of the set of space identifiers may for instance furthercomprise:

-   -   determining (e.g. finding) SNamei that matches with SNameA e.g.        one or more using string-matching methods.

For instance, such SNamei whose substring SNamei* may match exactly withsufficiently long substring SNameA* of SNameA. If no matching spaceidentifiers are found, it may for instance not be proceeded with one ormore further steps of the method according to the first exemplary aspectof the present invention.

If a respective space identifier e.g. with a matching name SNamei isdetermined (e.g. found), the respective location of the respectivemobile device Spacei can be considered to be the space of the at leastone appointment. Further, the location SLocationi can be considered tobe the location of the user respectively its mobile device during thetime of the at least one appointment, e.g. as represented by thevariable or parameters [TimeAstart, TimeAend].

According to an exemplary embodiment of all exemplary aspects of thepresent invention, the storing and/or providing the determined one ormore reference location estimates to be utilized as reference forfurther sensor data further comprises:

-   -   assigning the one or more pieces of fingerprint information        obtained or gathered during the time period to the location of        the space determined as the match.

The one or more pieces of fingerprint information may for instance beassigned to the location SLocationi of the space Spacei as well as tothe space Spacei. Thus, e.g. measurements (e.g. in the form of the oneor more pieces of fingerprint information) gathered (e.g. measured orcollected) by a respective mobile device during the time [TimeAstart+dt,TimeAend−dt] of the at least one appointment are linked to therespective location of the space in which the at least one appointmenttakes place.

According to an exemplary embodiment of all exemplary aspects of thepresent invention, the method further comprises:

-   -   determining one or more outliers of the determined one or more        reference location estimates at least partially based on a        comparison of one or more pieces of fingerprint information        obtained from one or more further mobile devices with the one or        more pieces of fingerprint information gathered or obtained; and    -   discarding such one or more pieces of fingerprint information of        the one or more pieces of fingerprint information gathered or        obtained in case a mismatch of pieces of fingerprint information        is determined by the comparison.

The one or more outliers determined may for instance be removed. In thisway, e.g. one or more pieces of fingerprint information that areconsidered to be measurement outliers can be discarded in order toachieve more accurate location estimates in a positioning. This may forinstance be done by comparing one or more pieces of fingerprintinformation gathered by a respective mobile device during the time[TimeAstart+dt, TimeAend−dt] of the at least one appointment with one ormore further pieces of fingerprint information gathered previously andwhich may for instance already be associated with Spacei/SLocationi.Thus, the one or more further pieces of fingerprint information may forinstance be already associated with one or more reference positionestimates indicative of a location at which the at least one appointmenttakes place. For instance, if a respective fingerprint informationmismatches with a certain amount (e.g. represented by a pre-definedthreshold value) further pieces of fingerprint information alreadyassociated with the Spacei/SLocationi, then such a respectivefingerprint information may for instance be discarded. If a proportionof discarded pieces of fingerprint information during the time period[TimeAstart+dt, TimeAend−dt] of the at least one appointment exceeds forinstance the pre-defined threshold, e.g. all the pieces of fingerprintinformation gathered by the respective mobile device from the time[TimeAstart+dt, TimeAend−dt] of the at least one appointment may forinstance be discarded.

These steps of the determining of one or more outliers and of thediscarding may for instance only be performable and/or controllable incase the method is performed and/or controlled by a server or servercloud since a mobile device may not have access to one or more pieces offingerprint information obtained from one or more further mobiledevices, e.g. one or more further mobile devices of users that take partin the at least one appointment.

An example embodiment according to the first exemplary aspect of thepresent invention may further comprise that the one or more pieces offingerprint information obtained from one or more further mobile devicesare determined (e.g. selected) based on one or more further calendarinformation obtained from the respective one or more further mobiledevices.

Further, one or more respective pieces of fingerprint information whichare the basis for determining one or more reference location estimatesmay for instance be considered to be equal to the location SLocationi ofthe Spacei.

According to an exemplary embodiment of all exemplary aspects of thepresent invention, the method further comprises:

-   -   storing and/or providing the respective pieces of fingerprint        information based on which the one or more reference location        estimates were determined.

The respective pieces of fingerprint information based on which the oneor more reference location estimates were determined may for instance bestored and/or provided in the same fashion as the one or more referencelocation estimates (see disclosure above).

The one or more determined reference location estimates may for instancebe respectively associated with or linked to the respective pieces offingerprint information gathered at or in the vicinity of the one ormore locations of the one or more reference location estimates.

According to an exemplary embodiment of all exemplary aspects of thepresent invention, the method further comprises:

-   -   generating (e.g. creating) an indoor radio map (e.g. a new or        updated radio map of the venue, or a part of it) at least        partially based on the one or more reference location estimates,        and on the respective pieces of fingerprint information.

The obtained (e.g. collected) one or more pieces of fingerprintinformation (e.g. in the form of one or more radio observation reports)may be used, at least partially, for generating or updating an indoorradio map (also referred to as radio positioning support map) of thearea and/or venue. Such an indoor radio map may for instance be used forpositioning purposes.

The apparatus performing and/or controlling the method according to thefirst exemplary aspect of the present invention may for instance beconfigured for generating or updating an indoor radio map of the areaand/or venue. The indoor radio map may for instance be generated orupdated at least partially based on a plurality of pieces of fingerprintinformation, e.g. gathered (e.g. measured) and provided (e.g. reported)to the apparatus by one or more mobile devices. Further, the indoorradio map may for instance be generated or updated based on thedetermined one or more pieces of reference location estimates enabling amore accurate positioning since the one or more pieces of referencelocation estimates represent a specific location that can be utilized tofine-tune a coarse location estimate. As disclosed in more detailsabove, each fingerprint information of the one or more pieces (e.g. aplurality) of fingerprint information may represent at least one of (i)an observation position, (ii) one or more radio signals observed by arespective mobile device of the one more mobile devices at theobservation position, (iii) one or more radio signal parameters of theobserved one or more radio signals measured by the respective mobiledevice or (iv) a combination thereof.

The indoor radio map may for instance require that it is generated atleast partially based on one or more pieces of fingerprint information.Further, the indoor radio maps may for instance be generated based onreference locations (e.g. as represented by the one or more referencelocation estimates) and pieces of fingerprint information. Moreprecisely, the indoor radio map may for instance be generated based onsuch pieces of fingerprint information of the one or more pieces offingerprint information, which have respectively an accurate locationreference e.g. associated with it, or which comprise an accuratelocation reference. Such an accurate location reference may for instancebe derivable from the determined one or more reference locationestimates.

According to an exemplary embodiment of all exemplary aspects of thepresent invention, the method further comprises:

-   -   storing and/or providing the generated indoor radio map.

The generated or updated indoor radio map may for instance be provided(e.g. transmitted) to one or more mobile devices, e.g. via acommunication network enabling the one or more mobile device todetermine (e.g. estimate) their respective (current) location at leastpartially based on the provided indoor radio map.

Alternatively or additionally, the indoor radio map may for instance bestored, e.g. by holding the indoor radio map available in a memory. Forexample, the indoor radio map may for instance be obtained (e.g.received) as a result of generating or updating the indoor radio map,and subsequently, the indoor radio map may for instance be stored in amemory.

According to an exemplary embodiment of all exemplary aspects of thepresent invention, the indoor radio map comprises or represents one ormore defined location information (e.g. respectively represented bylatitude-, longitude-coordinates, floor, optionally venue; or x-, y-, z-(e.g. altitude)-coordinates, optionally venue) of the one or more spaceslocated within the venue.

The features and example embodiments of the invention described abovemay equally pertain to the different aspects according to the presentinvention.

It is to be understood that the presentation of the invention in thissection is merely by way of examples and non-limiting.

Other features of the invention will become apparent from the followingdetailed description considered in conjunction with the accompanyingdrawings. It is to be understood, however, that the drawings aredesigned solely for purposes of illustration and not as a definition ofthe limits of the invention, for which reference should be made to theappended claims. It should be further understood that the drawings arenot drawn to scale and that they are merely intended to conceptuallyillustrate the structures and procedures described herein.

BRIEF DESCRIPTION OF THE DRAWINGS

In the figures show:

FIG. 1 a schematic block diagram of a system according to an exemplaryaspect of the present invention;

FIG. 2 a flowchart showing an example embodiment of a method accordingto the first exemplary aspect of the present invention;

FIG. 3a, 3b respective flowcharts, each showing an example embodiment ofa method according to the first exemplary aspect of the presentinvention;

FIG. 4 a flowchart showing an example embodiment of a method accordingto the first exemplary aspect of the present invention, which may forinstance be performed and/or controlled in addition to any of theflowcharts shown in FIG. 2, and/or FIG. 3a , 3 b;

FIG. 5 a flowchart showing an example embodiment that may for instancebe performed and/or controlled by a system according to an exemplaryaspect of the present invention;

FIG. 6 a schematic block diagram of an apparatus configured to performthe method according to the first exemplary aspect of the presentinvention;

FIG. 7 an indoor map as used by example embodiment according to allexemplary embodiments of the present invention; and

FIG. 8 user calendar information as used by example embodiment accordingto all exemplary embodiments of the present invention.

DETAILED DESCRIPTION OF SOME EXEMPLARY EMBODIMENTS

The following description serves to deepen the understanding of thepresent invention and shall be understood to complement and be readtogether with the description as provided in the above summary sectionof this specification.

FIG. 1 is a schematic high-level block diagram of a system 100 accordingto an example embodiment of the present invention.

Such a system 100 may for instance represent an architecture and/orenvironment that is/are configured, at least partially, to performand/or control one or more exemplary aspects of the present invention.

System 100 comprises a server 110, an optional database 120, one or moremobile devices 130 (e.g. a smartphone, tablet, wearable, IoT-device;wherein in FIG. 1 four mobile devices 130-1 to 130-4 are exemplaryshown), and a venue 150, which may also be an area. Inside the venue150, one or more radio nodes (e.g. Wi-Fi access points and/or BT and/orBLE beacons, to name but a few non-limiting examples) may for instancebe located and/or installed. In FIG. 1, such one or more radio nodes arenot shown. Based on signals sent by such one or more radio nodes, and/orone or more satellites e.g. of a cellular communication network (notshown in FIG. 1), to name but a few non-limiting examples, the one ormore mobile devices 130-1 to 130-4 may for instance gather (e.g.measure) one or more pieces of fingerprint information. At present, thearea and/or venue 150 is a building, such as an office building to namebut one non-limiting example. The building 150 comprises three floors150-G, 150-1, and 150-2. Each floor 150-G, 150-1, and 150-2 may forinstance comprise one or more spaces, such as rooms, public areas,meeting rooms, offices, or the like, to name but a few non-limitingexamples. For instance, as shown in FIG. 1, floor 150-G is divided intoor comprises three spaces 150-G-1, 150-G-2, and 150-G-3. Floor 150-1 isdivided into or comprises two spaces 150-1-1 and 150-1-2. Floor 150-2 isdivided into or comprises two spaces 150-2-1, and 150-2-2.

Each space of the building 150 may for instance be associated with arespective space identifier based on which the respective space can beidentified. For instance, Space 150-1-1 may for instance be a meetingroom. In the space 150-1-1, three mobile devices respectively theirusers are located, 130-1, 130-2, and 130-3. Space 150-G-3 may forinstance be an office, e.g. the office of the shown user. This user mayfor instance have the mobile device 130-4.

The server 110 may alternatively be embodied as a server cloud (e.g. aplurality of servers connected, e.g. via the internet, and/or acommunication network, and providing one or more services at leastpartially jointly). The server 110, which may for instance be embodiedas a positioning respectively navigation server, may for instance beconfigured to provide e.g. one or more indoor radio maps, and/or performand/or control positioning requests to determine (e.g. estimate) one ormore location estimates of one or more mobile devices (e.g. one or moremobile devices 130-1 to 130-4) to be determined (e.g. estimated). Theserver 110 may for instance be connected to the one or more mobiledevices 130, via a wirebound and/or wireless communication connection(e.g. according to the Wi-Fi, BT, BLE, and/or ZigBee communicationstandard, to name but a few non-limiting examples).

The optional database 120 may for instance be comprised by orconnectable to server 110. In case the optional database 120 iscomprised by server 110, server 110 and database 120 may form a singleentity. The database 120 may for instance comprise a memory, e.g. forstoring one or more pieces of calendar information, one or more coarselocation estimates, one or more sets of space identifiers, one or morereference location estimates, one or more pieces of fingerprintinformation, one or more outliers, one or more indoor radio maps, one ormore indoor maps, to name but a few non-limiting examples.

System 100 may for instance optionally comprise a communication network.The communication network may for instance be used for transmitting e.g.information between the server 110, the one or more mobile devices 130,and/or one or more radio nodes. The communication network may forinstance be the Internet and/or a cellular communication network, toname but a few non-limiting examples. It will be understood that such acommunication network may for instance be used for transmittinginformation between entities, devices, and/or units that are notexplicitly shown in FIG. 1 and/or described within the meaning of thepresent invention. Alternatively, communication network may for instancebe configured to transmit information for the entities, devices and/orunits that are explicitly shown in FIG. 1 and/or described within themeaning of the present invention.

Example embodiments according to all aspects of the present inventionenable a method, e.g. for deducing location(s) of one or more mobiledevices at least partially based on one or more pieces of calendarinformation obtainable from the one or more mobile devices.

For example, a user may enter a meeting in a calendar as comprised byhis respective mobile device. For instance, user of the mobile device130-4 may have entered in the mobile device 130-4 that a meeting takesplace in meeting room 150-1-1 at a certain time and date. As shown inFIG. 1, users respectively mobile devices 130-1 to 130-3 are already inthe meeting room. The users respectively mobile devices 130-1 to 130-3do also attend the respective meeting. Out of one or more pieces ofcalendar information, e.g. obtained by server 110, one or more spaceidentifiers, e.g. a space identifier of the meeting room 150-1-1 such asa character string representing the name of the meeting room 150-1-1 isextracted. Further, server 110 may for instance obtain (e.g. retrieve)an indoor map of the building 150, e.g. from the database 120. Then, itis analyzed (e.g. determined) whether one or more space identifiers asrepresented or comprised by the obtained radio map and associated withrespective spaces (e.g. one or more meeting rooms) covered by therespective indoor map match with one or more space identifiers asextracted from the one or more pieces of calendar information. Forinstance, in case a position is to be determined of one of the mobiledevices 130-1 to 130-4, the mobile devices 130-1 to 130-4 may forinstance gather one or more pieces of fingerprint information, which mayfor instance be obtained (e.g. received) by the server 110. Then, basedon the result of the determined match, a more accurate location estimatecan be determined in a positioning since it is derived that e.g. mobiledevices 130-1 to 130-4 take part in the meeting in meeting room 150-1-1.In case of the mobile device 130-4, the user of this mobile device mayfor instance be late for the meeting. Thus, in example embodiments ofthe method according to the first exemplary aspect of the presentinvention, a certain threshold for the start time and end time of themeeting taking place in meeting room 150-1-1 may for instance befactored in. For instance, after a lapse of a certain time period, oneor more further pieces of fingerprint information may for instance beobtained from the mobile device 130-4. Then, in the meantime, the userof mobile device 130-4 may for instance have moved into meeting room150-1-1 so that then based on the respective piece of calendarinformation, a reference location estimate representing the location ofthe meeting room 150-1-1 can be determined to be indicative of theposition of the mobile device 130-4 respectively its user.

FIG. 2 is a flowchart 200 showing an example embodiment of a methodaccording to the first exemplary aspect of the present invention. Thisflowchart 200 may for instance be performed by a server, or a servercloud, and/or a mobile device, e.g. server 110, and/or one of the mobiledevices 130-1 to 130-4 of FIG. 1.

In a first step 201, one or more pieces of calendar information areobtained. The one or more pieces of calendar information may forinstance be obtained by receiving the one or more pieces of calendarinformation from one or more mobile devices (e.g. mobile devices 130-1to 130-4 of FIG. 1) by the server. Further, the one or more pieces ofcalendar information may for instance be retrieved from a memory, e.g.in case flowchart 200 is performed and/or controlled by a respectivemobile device of the one or more mobile devices.

In an optional second step 202, one or more coarse location estimatesare determined (e.g. in case step 202 is performed and/or controlled bythe server), or triggered to be determined (e.g. in case step 202 isperformed and/or controlled by a respective mobile device). In thelatter case, e.g. a request for determining a coarse location estimateis sent by the respective mobile device, e.g. to the server, oralternatively, to a positioning server providing determining of one ormore coarse location estimate as a service. Of course, such apositioning server may for instance also provide (e.g. sent) thedetermined coarse location estimate to the server (e.g. server 110 ofFIG. 1).

In a third step 203, a set of space identifiers is extracted. Forinstance, at first, such a set of space identifiers may for instance beextracted out of the one or more pieces of calendar information obtainedin step 201. Then, at second, such a set of space identifiers may forinstance be extracted out of an indoor map, e.g. an indoor map of thebuilding 150 of FIG. 1. Then, in a fourth step 204 it is determined(e.g. checked or analyzed) whether or not there is match between thosespace identifiers derived from the one or more pieces of calendarinformation and the respective space identifiers derived from the indoormap. It will be understood that it may for instance also be possiblethat only a set of space identifiers is extracted out of an indoor map(e.g. obtained or retrieved from a memory, e.g. database 120 of FIG. 1).Then, the determining of the match may for instance be performed and/orcontrolled between the set of space identifiers and (e.g. directly) theone or more pieces of calendar information. Steps 203 and 204 may forinstance be performed by the server, or by a respective mobile device incase the flowchart 200 is performed and/or controlled by a respectivemobile device.

In case a match is found, the flowchart 200 may for instance continuewith step 205. In case no match is found, the flowchart 200 may forinstance not be continued to be performed and/or controlled.

In a fifth step 205, one or more reference location estimates aredetermined (e.g. in case step 205 is performed and/or controlled by theserver) or triggered to be determined (e.g. in case step 205 isperformed and/or controlled by a respective mobile device, and thismobile device e.g. request at a/the server to determine a respectivereference location estimate). A respective reference location estimatemay for instance be determined or triggered to be determined based onthe match found in step 204 since a respective reference locationestimate of the one or more reference location estimates is indicativeof a location of the space that was determined to be a match (step 204),wherein the location to be represented by the respective referencelocation estimate of the one or more reference location estimatescorresponds to the location of the space (found by the step 204) that isderived from the respective indoor map e.g. obtained as disclosed withrespect to step 203.

In an optional sixth step 206, the one or more determined referencelocation estimates are stored and/or provided. The one or moredetermined reference location estimates may for instance be stored in amemory, e.g. comprised by or connectable to the apparatus performingand/or controlling the flowchart 200, e.g. a database such as database120 of FIG. 1 in case the flowchart 200 is performed and/or controlledby the server 110 of FIG. 1. Further, the one or more determinedreference location estimates may for instance be stored in a memory,e.g. comprised by or connectable to a respective mobile device in casethe flowchart 200 is e.g. performed and/or controlled by one of themobile devices 130-1 to 130-4 of FIG. 1.

The one or more determined reference location estimates may for instancebe provided, e.g. to one or more further entities (e.g. not shown inFIG. 1), and/or to one or more mobile devices (e.g. one or more of themobile devices 130-1 to 130-4 of FIG. 1) from the server 110 of FIG. 1,or to the server 110 of FIG. 1 from one or more mobile devices (e.g. oneor more of the mobile devices 130-1 to 130-4 of FIG. 1). The one or moredetermined reference location estimates may for instance be provided bysending the one or more determined reference location estimates, e.g.directly to one or more intended recipients (to the one or more mobiledevices, or to the server, see disclosure above), or to another entitythat may for instance relay the one or more determined referencelocation estimates to one or more intended recipients.

FIG. 3a is a flowchart 300 a showing an example embodiment of a methodaccording to the first exemplary aspect of the present invention in casethe method according to the first exemplary aspect of the presentinvention is performed and/or controlled by a server (e.g. server 110 ofFIG. 1).

Further, FIG. 3b is a flowchart 300 b showing an example embodiment of amethod according to the first exemplary aspect of the present inventionin case the method according to the first exemplary aspect of thepresent invention is performed and/or controlled by a mobile device(e.g. one of the mobile devices 130-1 to 130-4 of FIG. 1).

In the following, comparable steps as to be performed and/or controlledby a server or server cloud (flowchart 300 a of FIG. 3a ) or, inalternative, by a mobile device (flowchart 300 b of FIG. 3b ) aredescribed in relation to each other, in particular pointing out thedifferences.

In a first step 301 b, the one or more pieces of calendar informationare retrieved, e.g. from a memory comprised by or connectable to theapparatus (e.g. mobile device) performing and/or controlling flowchart300 a. In contrast in step 301 a, in case that the method according tothe first exemplary aspect of the present invention is performed and/orcontrolled by a server, the one or more pieces of calendar informationare received, e.g. from one or more mobile devices.

In an optional step 302 a, the server determines one or more coarselocation estimates. In contrast, in optional step 302 b the one or morecoarse location estimates may either be determined by the respectivemobile device, or the respective mobile device may trigger (e.g. aserver, such as server 110 of FIG. 1) to determine the one or morecoarse location estimates.

In an optional step 303 b, the respective mobile device obtains (e.g.receives) an indoor map (of a venue), e.g. in case such an indoor map ofthe venue was not obtained earlier.

In a step 304 a respectively 304 b, a set of space identifiers isextracted by the server respectively the respective mobile device. Theextraction of the set of space identifiers can be performed and/orcontrolled in the same way as described with respect to step 203 of FIG.2.

In a step 305 a respectively 305 b, it is determined (e.g. checked oranalyzed) if one or more space identifiers of the calendar information(e.g. comprised or represented by the one or more pieces of calendarinformation) match e.g. one or more space identifiers of the set ofspace identifiers, as described with respect to step 204 of FIG. 2.

In a step 306 a respectively 306 b, one or more reference locationestimates are determined by the server, or determined by the respectivemobile device, or alternatively, triggered by the respective mobiledevice, e.g. to be determined by a server, such as server 110 of FIG. 1.

In an optional step 307 a respectively 307 b, the one or more determinedreference location estimates are stored (e.g. in a memory respectivelycomprised by or connectable to the server, or the respective mobiledevice). Additionally or alternatively, the one or more determinedreference location estimates may for instance be provided (e.g. sent) toone or more other entities, in the same way as described with respect tostep 206 of FIG. 2

FIG. 4 is a flowchart 400 showing an example embodiment of a methodaccording to the first exemplary aspect of the present invention, whichmay for instance be performed and/or controlled in addition to any ofthe flowcharts shown in FIG. 2, and/or FIG. 3a, 3b . Flowchart 400 mayfor instance be performed and/or controlled by the respective apparatusalso performing and/or controlling the respective flowchart 200, 300 a,300 b of FIG. 2, 3 a, 3 b.

All of the steps 401 to 405 are optional steps. Further, all of thesteps 401 to 405 may for instance be performed and/or controlled priorand/or subsequential to, and/or in parallel to any of the steps ascomprised by the flowcharts 200, 300 a, 300 b of FIG. 2, 3 a, 3 b. Itwill further be understood that any of the steps 401 to 405 may forinstance be performed and/or controlled one or more times (e.g. aplurality of times).

In a step 401, one or more pieces of fingerprint information areobtained (e.g. received in case step 401 is performed and/or controlledby a server (e.g. server 110 of FIG. 1). Alternatively, the one or morepieces of fingerprint information are gathered (e.g. measured) in casestep 401 is performed and/or controlled by a respective mobile device(e.g. one of the mobile devices 130-1 to 130-4 of FIG. 1).

In a step 402, the one or more pieces of fingerprint information of step401 are assigned to a/the respective location of a/the space determinedas a/the match in any of the steps 204 of FIG. 2, 305 a of FIG. 3a,and/or 305b of FIG. 3b . The assigning may for instance be stored, e.g.in a memory. The memory may for instance be the same memory as used instep 206 o FIG. 2, 307 a of FIG. 3a and/or 307 b of FIG. 3b for storingthe one or more determined reference location estimates.

In a step 403, one or more outliers are determined at least partiallybased on the one or more reference location estimates (see step 205 ofFIG. 2, step 306 a of FIG. 3a , step 306 b of FIG. 3b ).

In a step 404, e.g. based on the result(s) of step 403, such one or morepieces of fingerprint information (see step 401) that e.g. do not matchother pieces of fingerprint information are discarded. For instance, oneor more pieces of fingerprint information may for instance comprise orrepresent identifiers of one or more radio nodes basically gathered atthe same location (e.g. same space of an area and/or a venue) andgathered by different mobile devices do not match. Then, such one ormore pieces of fingerprint information not matching may for instance bediscarded (e.g. by deleting the respective one or more pieces offingerprint information, to name but one non-limiting example).

In a step 405, an indoor radio map is generated (e.g. determined orcreated). For instance, in case an indoor radio map for a certain areaand/or venue is available, the indoor radio map generated in step 405may for instance update the previous one. The indoor radio map of step405 may for instance be more accurate since e.g. certain match(es)determined (see step 204 of FIG. 2, 305 a of FIG. 3a, 305b of FIG. 3b )and/or one or more pieces of reference location estimates (see step 205of FIG. 2, 306 a of FIG. 3a, 306b of FIG. 3b ) may for instance beconsidered and be comprised or represented respectively in the generatedindoor radio map.

FIG. 5 is a flowchart 500 showing an example embodiment of a methodaccording to the first exemplary aspect of the present invention that isto be performed and/or controlled by a system according to exampleembodiments of all exemplary aspects of the present invention. Forinstance, flowchart 500 may for instance be performed and/or controlledby the system 100 shown in FIG. 1.

In FIG. 5, a system such as system 100 of FIG. 1 performing and/orcontrolling an example embodiment according to all exemplary aspects ofthe present invention is shown. As shown in FIG. 5, a server such asserver 110 of FIG. 1 performs and/or controls the method of the firstexemplary aspect of the present invention. One or more mobile deviceswhich respective steps are shown from top to bottom on the right handside as a column view in FIG. 5. It will be understood that a pluralityof mobile devices (e.g. at least two mobile devices) may for instanceinteract with the server, which steps to be performed and/or controlledare shown from top to bottom on the left hand side as a column view inFIG. 5.

The steps performed and/or controlled by the server (e.g. server 110 ofFIG. 1) are referenced to by the same reference numerals as shown inflowchart 300 a of FIG. 3a . The server 110 obtains one or more piecesof calendar information from the respective mobile device (e.g. one ofthe mobile devices 130 of FIG. 1), or from a plurality of mobile devices(e.g. mobile devices 130-1 to 130-4 of FIG. 1). The one or more piecesof calendar information may for instance be obtained (e.g. received) atany given time, as indicated in FIG. 5 by the horizontal dashed line“Meeting Start” so that the one or more pieces of calendar informationmay for instance be sent by the respective mobile device(s) 130 prior toa meeting to the server 110.

Then, after a meeting has started, one or more pieces of fingerprintinformation may for instance be gathered (e.g. measured) by therespective mobile device(s) 130 and then provided (e.g. sent) from therespective mobile device(s) 130 to the server 110.

The server 110 can then perform optional step 302 a of determining oneor more coarse location estimates, e.g. at least partially based on theone or more pieces of fingerprint information obtained (e.g. received)from the respective mobile device(s) 130.

Then, the server 110 can extract a set of space identifiers out of theone or more pieces of calendar information, as indicated by referencenumeral 304 a. It will be understood that this step 304 a can beperformed earlier, e.g. after obtaining the one or more pieces ofcalendar information, and/or prior to the meeting start, to name but afew non-limiting examples.

As indicated by reference numeral 305 a, the server 110 determines (e.g.checks or analyzes) if one or more space identifiers of the calendarinformation (e.g. comprised or represented by the one or more pieces ofcalendar information) match one or more space identifiers of the set ofspace identifiers, e.g. as extracted out of an indoor map of an areaand/or venue. In case such a match is not determined (e.g. found), theflowchart of FIG. 5 may for instance end, or alternatively, one or more(e.g. new or further) pieces of fingerprint information may for instancebe requested to be obtained from the respective mobile device(s) 130.

In case such a match is determined, step 306 a can be performed and/orcontrolled by the server 110 so that the server 110 determines one ormore reference location estimates being indicative of a location of aspace in an area and/or venue (e.g. venue 150 of FIG. 1).

In an optional step 307 a, the one or more reference location estimatesof step 306 a can be stored in a memory (e.g. comprised by orconnectable to the server 110). Additionally or alternatively, the oneor more reference location estimates of step 306 a may for instance beprovided (e.g. output or sent), e.g. to the respective mobile device(s)130 so that the respective mobile device(s) 130 can obtain (e.g.receive) the respective one or more reference location estimates asdetermined by the server 110.

At any time subsequential to the meeting start, the meeting can end.Exemplary, the end of the meeting is indicated in FIG. 5 after optionalstep 307 a is performed and/or controlled by server 110.

FIG. 6 is a schematic block diagram of an apparatus 600 according to anexemplary aspect of the present invention, which may for instancerepresent server 110 of FIG. 1. Alternatively, the schematic blockdiagram of the apparatus 600 according to an exemplary aspect of thepresent invention may for instance represent one of the mobile devices130-1 to 130-4 of FIG. 1.

Apparatus 600 comprises a processor 610, working memory 620, programmemory 630, data memory 640, communication interface(s) 650, an optionaluser interface 660. In case apparatus 600 represents one of the mobiledevices 130-1 to 130-4 of FIG. 1, sensor(s) 670 can optionally becomprised.

Apparatus 600 may for instance be configured to perform and/or controlor comprise respective means (at least one of 610 to 670) for performingand/or controlling the method according to the first exemplary aspect ofthe present invention. Apparatus 600 may as well constitute an apparatuscomprising at least one processor (610) and at least one memory (620)including computer program code, the at least one memory and thecomputer program code configured to, with the at least one processor,cause an apparatus, e.g. apparatus 600 at least to perform and/orcontrol the method according to the first exemplary aspect of theinvention of the present invention.

Processor 610 may for instance comprise a calendar information obtainer611-1 as a functional and/or structural unit. Calendar informationobtainer 611-1 may for instance be configured to obtain one or morepieces of calendar information (see step 201 of FIG. 2, step 301 a ofFIG. 3a , step 301 b of FIG. 3b ).

Processor 610 may for instance comprise an optional coarse locationestimate determiner 611-2 as a functional and/or structural unit.Optional coarse location estimate determiner 611-2 may for instance beconfigured to determine one or more coarse location estimates (see step202 of FIG. 2, step 302 a of FIG. 3a , step 302 b of FIG. 3b ).

Processor 610 may for instance comprise a set of space identifierextractor 611-3 as a functional and/or structural unit. Set of spaceidentifier extractor 611-3 may for instance be configured to extract oneor more sets of space identifiers (see step 203 of FIG. 2, step 304 a ofFIG. 3a , step 304 b of FIG. 3b ).

Processor 610 may for instance comprise a space matcher 611-4 as afunctional and/or structural unit. Space matcher 611-4 may for instancebe configured to match or check whether one or more space identifiers ofone or more pieces of calendar information match one or more sets ofspace identifier (e.g. an extracted set of space identifiers of set ofspace identifier extractor 611-3; see step 204 of FIG. 2, step 305 a ofFIG. 3a , step 305 b of FIG. 3b ).

Processor 610 may for instance comprise a reference location estimatedeterminer 611-5 as a functional and/or structural unit. Referencelocation estimate determiner 611-5 may for instance be configured todetermine one or more reference location estimates (see step 205 of FIG.2, step 306 a of FIG. 3a , step 306 b of FIG. 3b ).

Processor 610 may for instance comprise an optional fingerprintinformation obtainer/gatherer 611-6 as a functional and/or structuralunit. Optional fingerprint information obtainer/gatherer 611-6 may forinstance be configured to obtain and/or gather one or more pieces offingerprint information (see step 401 of FIG. 4).

Processor 610 may for instance comprise an optional fingerprintinformation assigner 611-7 as a functional and/or structural unit.Optional fingerprint information assigner 611-7 may for instance beconfigured to assign one or more pieces of fingerprint to one or morelocations of one or more determined spaces (see step 402 of FIG. 4).

Processor 610 may for instance comprise an optional outlier determiner611-8 as a functional and/or structural unit. Optional outlierdeterminer 611-8 may for instance be configured to determine one or moreoutliers of one or more determined reference location estimates (seestep 403 of FIG. 4).

Processor 610 may for instance comprise an optional discarder 611-9 as afunctional and/or structural unit. Optional discarder 611-9 may forinstance be configured to discard one or more pieces of fingerprintinformation (see step 404 of FIG. 4).

Processor 610 may for instance comprise an optional indoor radio mapgenerator 611-10 as a functional and/or structural unit. Optional indoorradio map generator 611-10 may for instance be configured to generate(e.g. determine or create) one or more indoor radio maps (see step 405of FIG. 4).

Processor 610 may for instance further control the memories 620 to 640,the communication interface(s) 650, the optional user interface 660 andthe optional sensor(s) 670.

Processor 610 may for instance execute computer program code stored inprogram memory 630, which may for instance represent a computer readablestorage medium comprising program code that, when executed by processor610, causes the processor 610 to perform the method according to thefirst exemplary aspect of the present invention.

Processor 610 (and also any other processor mentioned in thisspecification) may be a processor of any suitable type. Processor 610may comprise but is not limited to one or more microprocessor(s), one ormore processor(s) with accompanying one or more digital signalprocessor(s), one or more processor(s) without accompanying digitalsignal processor(s), one or more special-purpose computer chips, one ormore field-programmable gate array(s) (FPGA(s)), one or morecontroller(s), one or more application-specific integrated circuit(s)(ASIC(s)), or one or more computer(s). The relevant structure/hardwarehas been programmed in such a way to carry out the described function.Processor 610 may for instance be an application processor that runs anoperating system.

Program memory 630 may also be included into processor 610. This memorymay for instance be fixedly connected to processor 610, or be at leastpartially removable from processor 610, for instance in the form of amemory card or stick. Program memory 630 may for instance benon-volatile memory. It may for instance be a FLASH memory (or a partthereof), any of a ROM, PROM, EPROM and EEPROM memory (or a partthereof) or a hard disc (or a part thereof), to name but a few examples.Program memory 630 may also comprise an operating system for processor610. Program memory 630 may also comprise a firmware for apparatus 600.

Apparatus 600 comprises a working memory 620, for instance in the formof a volatile memory. It may for instance be a Random Access Memory(RAM) or Dynamic RAM (DRAM), to give but a few non-limiting examples. Itmay for instance be used by processor 610 when executing an operatingsystem and/or computer program.

Data memory 640 may for instance be a non-volatile memory. It may forinstance be a FLASH memory (or a part thereof), any of a ROM, PROM,EPROM and EEPROM memory (or a part thereof) or a hard disc (or a partthereof), to name but a few examples. Data memory 640 may for instancestore one or more pieces of calendar information, one or more coarselocation estimates, one or more sets of space identifiers, one or morereference location estimates, one or more pieces of fingerprintinformation, one or more outliers, one or more indoor radio maps, one ormore radio maps, to name but a few non-limiting examples.

Communication interface(s) 650 enable apparatus 600 to communicate withother entities, e.g. with server 110 of FIG. 1 in case apparatus 600represents one of the mobile devices 130-1 to 130-4 of FIG. 1.Communication interface(s) 650 enable apparatus 600 to communicate withother entities, e.g. with one of the mobile devices 130-1 to 130-4 ofFIG. 1 in case apparatus 600 represents server 110 of FIG. 1. Thecommunication interface(s) 650 may for instance comprise a wirelessinterface, e.g. a cellular radio communication interface and/or a WLANinterface) and/or wire-bound interface, e.g. an IP-based interface, forinstance to communicate with entities via the Internet. Communicationinterface(s) may enable apparatus 600 to communicate with otherentities, for instance with one or more radio nodes, or with one or morebase stations of a cellular communication network, or the like, to namebut a few non-limiting examples.

User interface 660 is optional and may comprise a display for displayinginformation to a user and/or an input device (e.g. a keyboard, keypad,touchpad, mouse, etc.) for receiving information from a user.

Sensor(s) 670 are optional and may for instance comprise a gyroscope, anaccelerometer, an inertial sensor, barometric sensor, e.g. to gather(e.g. measure) respective information e.g. indicative of a positionand/or orientation and/or velocity of the apparatus 600 in itssurrounding, and/or an (e.g. absolute or relative) altitude value of theapparatus 600, to name but a few non-limiting examples. Sensor(s) 670may for instance be comprised by the apparatus 600 in case apparatus 600represents one of the mobile devices 130 of FIG. 1.

Some or all of the components of the apparatus 600 may for instance beconnected via a bus. Some or all of the components of the apparatus 600may for instance be combined into one or more modules.

The following embodiments shall also be considered to be disclosed:

Embodiment 1

An apparatus comprising at least one processor and at least one memoryincluding computer program code, the at least one memory and thecomputer program code configured to, with the at least one processor,cause the apparatus to at least perform:

-   -   obtaining one or more pieces of calendar information indicative        of at least one appointment taking place in a space;    -   extracting a set of space identifiers representing one or more        spaces of the venue, wherein the one or more spaces respectively        their one or more space identifiers are extracted based on an        indoor map of the venue;    -   determining or triggering determining whether at least a part of        the set of space identifiers or one or more spaces of the set of        space identifiers matches or match the at least one space as        represented by the obtained one or more pieces of calendar        information; and in case such a match is found:    -   determining one or more reference location estimates, wherein a        respective reference location estimate of the one or more        reference location estimates is indicative of a location of the        space that was determined to be a match, wherein the location of        the space is derived from the indoor map.

Embodiment 2

The apparatus according to embodiment 1, the at least one memory and thecomputer program code configured to, with the at least one processor,cause the apparatus further to perform:

-   -   determining or triggering determining one or more coarse        location estimates.

Embodiment 3

The apparatus according to any of the preceding embodiments, wherein thecalendar information is further indicative of a time period of the atleast one appointment.

Embodiment 4

The apparatus according to any of the preceding embodiments, wherein thecalendar information is associated with a user of a mobile device.

Embodiment 5

The apparatus according to any of the preceding embodiments, wherein thespace of the venue is represented by a character string.

Embodiment 6

The apparatus according to any of the embodiments 3 to 5, wherein thedetermining of the one or more coarse location estimates furthercomprises:

-   -   obtaining or gathering one or more pieces of fingerprint        information, wherein the obtaining or the gathering is performed        and/or controlled during the time period of the at least one        appointment; and    -   wherein the one or more coarse location estimates are determined        at least partially based on the one or more pieces of        fingerprint information.

Embodiment 7

The apparatus according to embodiment 6, wherein the set of spaceidentifiers is extracted further based on the one or more coarselocation estimates, wherein the set of space identifiers comprises oneor more spaces located in the vicinity of the one or more coarselocation estimates.

Embodiment 8

The apparatus according to any of the preceding embodiments, the atleast one memory and the computer program code configured to, with theat least one processor, cause the apparatus further to perform:

-   -   storing and/or providing the determined one or more reference        location estimates to be utilized as reference for further        sensor data.

Embodiment 9

The apparatus according to embodiment 8, wherein the storing and/orproviding the determined one or more reference location estimates to beutilized as reference for further sensor data further comprises:

-   -   assigning the one or more pieces of fingerprint information        obtained or gathered during the time period to the location of        the space determined as the match.

Embodiment 10

The apparatus according to any of the embodiments 6 to 9, the at leastone memory and the computer program code configured to, with the atleast one processor, cause the apparatus further to perform:

-   -   determining one or more outliers of the determined one or more        reference location estimates at least partially based on a        comparison of one or more pieces of fingerprint information        obtained from one or more further mobile devices with the one or        more pieces of fingerprint information gathered or obtained; and    -   discarding such one or more pieces of fingerprint information of        the one or more pieces of fingerprint information gathered or        obtained in case a mismatch of pieces of fingerprint information        is determined by the comparison.

Embodiment 11

The apparatus according to any of the embodiments 6 to 10, the at leastone memory and the computer program code configured to, with the atleast one processor, cause the apparatus further to perform:

-   -   storing and/or providing the respective pieces of fingerprint        information based on which the one or more reference location        estimates were determined.

Embodiment 12

The apparatus according to any of the embodiments 6 to 11, the at leastone memory and the computer program code configured to, with the atleast one processor, cause the apparatus further to perform:

-   -   generating an indoor radio map at least partially based on the        one or more reference location estimates, and on the respective        pieces of fingerprint information.

Embodiment 13

The apparatus according to any of the preceding embodiments, wherein theindoor radio map comprises or represents one or more defined locationinformation of the one or more spaces located within the venue.

Embodiment 14

An apparatus comprising at least one processor and at least one memoryincluding computer program code, the at least one memory and thecomputer program code configured to, with the at least one processor,cause an apparatus at least to perform and/or control the method of anyof the claims 1 to 13.

Embodiment 15

A tangible computer-readable medium storing computer program code, thecomputer program code when executed by a processor causing an apparatusto perform and/or control:

-   -   obtaining one or more pieces of calendar information indicative        of at least one appointment taking place in a space;    -   extracting a set of space identifiers representing one or more        spaces of the venue, wherein the one or more spaces respectively        their one or more space identifiers are extracted based on an        indoor map of the venue;    -   determining or triggering determining whether at least a part of        the set of space identifiers or one or more spaces of the set of        space identifiers matches or match the at least one space as        represented by the obtained one or more pieces of calendar        information; and in case such a match is found:    -   determining one or more reference location estimates, wherein a        respective reference location estimate of the one or more        reference location estimates is indicative of a location of the        space that was determined to be a match, wherein the location of        the space is derived from the indoor map.

Embodiment 16

A tangible computer-readable medium storing computer program code, thecomputer program code when executed by a processor causing an apparatusto perform and/or control the method of any of the claims 1 to 13.

Example embodiments according to all exemplary aspect of the presentinvention enable a non-real-time method e.g. for deducing the location(=numerical representation of location in terms of e.g.Lat/Lon/venue/floor) of a device based on

-   -   the space information (e.g. space identifier) from the user        calendar (represented by one or more pieces of calendar        information), e.g. being indicative of where the user of a        respective mobile device is supposed to be and when; and    -   information about the locations of the meeting rooms,        lecture/class rooms, which location information may for instance        be extracted from one or more indoor maps.

Information about person'smeetings/appointments/lectures/classes/seminars with the time detailedinformation about the space, for instance where e.g. the meeting is,exists in various kind of software applications (e.g. Outlook, Googlecalendar, etc.) such information may include at least time of the eventand name of the space of the event (e.g. meeting room name).

Also, there exist various indoor maps, e.g. provided by HERE, whichcontain names of the spaces/meeting rooms; lecture rooms etc.

According to the Proposed Method

1. the name SNameA of the space for the appointment is determined basedon the calendar information

2. at the time of appointment device determines its coarse location

3. A set of space names {SName1, SName2, . . . } and their locations{SLocation1, SLocation2, . . . } are extracted from the indoor maps forthe vicinity of the device coarse location

4. extracted space names {SName1, SName2, . . . } are compared againstthe SNameA of the space of the user appointment

5. if one of the extracted space names SNamei match with the nameSNameA, user is at the location of the space associated with thematching name. This provides the numerical (e.g. Lat/Lon/floor)information about the user location.

6. The estimated location of the device during appointment is used toreference device sensor data, such as Wi-Fi/BLE/cellular measurements.Georeferenced radio measurements be used for e.g. radio map generationfor indoor positioning.

In summary, this method provides a way to learn geo-referenced radiomeasurements from indoors, where traditional positioning methods fail.

The steps of the proposed respectively above disclosed method will beexplained in detail below:

1. Obtain information about the user appointment, including:

-   -   time period of the appointment [TimeAstart, TimeAend]    -   Name of the appointment space SNameA (e.g. a meeting room name)

2. Collect and store sensor data from the user device during the timeperiod [TimeAstart, TimeAend], particularly Wi-Fi and BLE measurements

3. Determine coarse device locations [XTimeA1, XTimeA2, . . . ] duringthe time of appointment based on GNSS/Wi-Fi/cellular signals. It isnoted that this step only facilitates the further search but is notstrictly necessary, it is also possible that location of the spacealready exist in the meeting details).

4. Obtain list of spaces {Space1, Space2, . . . } located in thevicinity of locations [XTimeA1, XTimeA2, . . . XTimeAK]. The listconsists of the space names {SName1, SName2, . . . } and space locations{SLocation1, SLocation2, . . . }. The list is obtained from the indoormap. Circle of pre-defined radius around median of locations [XTimeA1,XTimeA2, . . . XTimeAK] can be considered as the area of proximity.

5. Find SNamei that matches with SNameA using string-matching methods.For instance, such SNamei whose substring SNamei* match exactly withsufficiently long substring SNameA*of SNameA. If no matching namesfound, do not proceed with further steps.

6. If space with matching name SNamei is found, the Spacei is the spaceof a user appointment and the location SLocationi is the location of theuser and hence the user device during the time of the appointment[TimeAstart, TimeAend].

It is noted that to account for a user to come to the meeting later orleaving earlier from the meeting can be account for by considered asmall time interval [TimeAstart+dt, TimeAend−dt]. Additionally, sensordata can be used to estimate the time when user is in the meeting. Thiscan be done by considering only the time periods when user does not movesignificantly or does not make steps, according to accelerationmeasurements.

7. Determine locations of the measurements collected by the deviceduring time [TimeAstart+dt, TimeAend−dt] to be the location SLocationiof the space Spacei. Also, assign measurements collected by the deviceduring the time [TimeAstart+dt, TimeAend−dt] to the location SLocationiof the space Spacei as well as to the space Spacei.

8. Remove the measurements outliers. This can be done by comparing themeasurements made by the device during the time [TimeAstart+dt,TimeAend−dt] with the measurements already associated withSpacei/SLocationi. For example, if measurement shows mismatch withenough measurements already associated with the Spacei/SLocationi, thensuch a measurement can be discarded. If proportion of discardedmeasurements during time period [TimeAstart+dt, TimeAend−dt] exceedspre-defined thresholds, all the device measurements from [TimeAstart+dt,TimeAend−dt] can be discarded. As an example, Wi-Fi/BLE measurements canbe compared/matched in terms of Euclidean norm between the measurementsvectors.

9. Device measurements whose reference is determined to be equal to thelocation SLocationi of the Spacei as well as the measurementscontextually assigned to the Spacei can be further used for generating aradio map in the proximity of the Spacei.

Alternatively, such measurements can be used to determine whichWi-Fi/BLE radio nodes are located in a close proximity to the Spacei orlocated inside Spacei.

FIG. 7 shows a venue map (e.g. indoor map) and example data from acalendar that can be used by the method as presented. Based on theinformation from the venue map presented on the FIG. 7, and usercalendar information presented in the FIG. 8, it is possible todetermine location of the user within a building during time of theappointments:

-   -   Meeting room 1 (South-west corner), 17:00-18:00, 22.03.2019    -   Meeting room 2 (South-central part), 18:00-19:00, 22.03.2019    -   Meeting room 3 (North-east corner), 19:00-20:00, 22.03.2019

Therefore, geo-reference Wi-Fi/Bluetooth radio data can be collected atthese spaces by the user devices during the indicated times.

Example embodiments according to all aspects of the present inventionprovide additional means for device localization in indoor environments.Potentially improves indoor positioning in “smart office” applications.The Example embodiments enable in particular improved indoor positioningresults in case the area of the space is small, such as in an officebuilding.

In the present specification, any presented connection in the describedembodiments is to be understood in a way that the involved componentsare operationally coupled. Thus, the connections can be direct orindirect with any number or combination of intervening elements, andthere may be merely a functional relationship between the components.

Moreover, any of the methods, processes and actions described orillustrated herein may be implemented using executable instructions in ageneral-purpose or special-purpose processor and stored on acomputer-readable storage medium (e.g., disk, memory, or the like) to beexecuted by such a processor. References to a ‘computer-readable storagemedium’ should be understood to encompass specialized circuits such asFPGAs, ASICs, signal processing devices, and other devices.

The expression “A and/or B” is considered to comprise any one of thefollowing three scenarios: (i) A, (ii) B, (iii) A and B. Furthermore,the article “a” is not to be understood as “one”, i.e. use of theexpression “an element” does not preclude that also further elements arepresent. The term “comprising” is to be understood in an open sense,i.e. in a way that an object that “comprises an element A” may alsocomprise further elements in addition to element A.

It will be understood that all presented embodiments are only exemplary,and that any feature presented for a particular example embodiment maybe used with any aspect of the invention on its own or in combinationwith any feature presented for the same or another particular exampleembodiment and/or in combination with any other feature not mentioned.In particular, the example embodiments presented in this specificationshall also be understood to be disclosed in all possible combinationswith each other, as far as it is technically reasonable and the exampleembodiments are not alternatives with respect to each other. It willfurther be understood that any feature presented for an exampleembodiment in a particular category (method/apparatus/computerprogram/system) may also be used in a corresponding manner in an exampleembodiment of any other category. It should also be understood thatpresence of a feature in the presented example embodiments shall notnecessarily mean that this feature forms an essential feature of theinvention and cannot be omitted or substituted.

The statement of a feature comprises at least one of the subsequentlyenumerated features is not mandatory in the way that the featurecomprises all subsequently enumerated features, or at least one featureof the plurality of the subsequently enumerated features. Also, aselection of the enumerated features in any combination or a selectionof only one of the enumerated features is possible. The specificcombination of all subsequently enumerated features may as well beconsidered. Also, a plurality of only one of the enumerated features maybe possible.

The sequence of all method steps presented above is not mandatory, alsoalternative sequences may be possible. Nevertheless, the specificsequence of method steps exemplarily shown in the figures shall beconsidered as one possible sequence of method steps for the respectiveembodiment described by the respective figure.

The invention has been described above by means of example embodiments.It should be noted that there are alternative ways and variations whichare obvious to a skilled person in the art and can be implementedwithout deviating from the scope of the appended claims.

That which is claimed is:
 1. A method, comprising: obtaining one or morepieces of calendar information indicative of at least one appointmenttaking place in a space; extracting a set of space identifiersrepresenting one or more spaces of the venue, wherein the one or morespaces respectively their one or more space identifiers are extractedbased on an indoor map of the venue; determining or triggeringdetermining whether at least a part of the set of space identifiers orone or more spaces of the set of space identifiers matches or match theat least one space as represented by the obtained one or more pieces ofcalendar information; and in case such a match is found: determining oneor more reference location estimates, wherein a respective referencelocation estimate of the one or more reference location estimates isindicative of a location of the space that was determined to be a match,wherein the location of the space is derived from the indoor map.
 2. Themethod according to claim 1, further comprising: determining ortriggering determining one or more coarse location estimates.
 3. Themethod according to claim 1, wherein the calendar information is furtherindicative of a time period of the at least one appointment.
 4. Themethod according to claim 1, wherein the calendar information isassociated with a user of a mobile device.
 5. The method according toclaim 1, wherein the space of the venue is represented by a characterstring.
 6. The method according to claim 3, wherein the determining ofthe one or more coarse location estimates further comprises: obtainingor gathering one or more pieces of fingerprint information, wherein theobtaining or the gathering is performed and/or controlled during thetime period of the at least one appointment; and wherein the one or morecoarse location estimates are determined at least partially based on theone or more pieces of fingerprint information.
 7. The method accordingto claim 6, wherein the set of space identifiers is extracted furtherbased on the one or more coarse location estimates, and wherein the setof space identifiers comprises one or more spaces located in thevicinity of the one or more coarse location estimates.
 8. The methodaccording to claim 1, further comprising: storing and/or providing thedetermined one or more reference location estimates to be utilized asreference for further sensor data.
 9. The method according to claim 8,wherein the storing and/or providing the determined one or morereference location estimates to be utilized as reference for furthersensor data further comprises: assigning the one or more pieces offingerprint information obtained or gathered during the time period tothe location of the space determined as the match.
 10. The methodaccording to claim 6, further comprising: determining one or moreoutliers of the determined one or more reference location estimates atleast partially based on a comparison of one or more pieces offingerprint information obtained from one or more further mobile deviceswith the one or more pieces of fingerprint information gathered orobtained; and discarding such one or more pieces of fingerprintinformation of the one or more pieces of fingerprint informationgathered or obtained in case a mismatch of pieces of fingerprintinformation is determined by the comparison.
 11. The method according toclaim 6, further comprising: storing and/or providing the respectivepieces of fingerprint information based on which the one or morereference location estimates were determined.
 12. The method accordingto claim 6, further comprising: generating an indoor radio map at leastpartially based on the one or more reference location estimates, and onthe respective pieces of fingerprint information.
 13. The methodaccording to claim 1, wherein the indoor radio map comprises orrepresents one or more defined location information of the one or morespaces located within the venue.
 14. An apparatus comprising at leastone processor and at least one memory including computer program code,the at least one memory and the computer program code configured to,with the at least one processor, cause the apparatus at least to: obtainone or more pieces of calendar information indicative of at least oneappointment taking place in a space; extract a set of space identifiersrepresenting one or more spaces of the venue, wherein the one or morespaces respectively their one or more space identifiers are extractedbased on an indoor map of the venue; determine or trigger determiningwhether at least a part of the set of space identifiers or one or morespaces of the set of space identifiers matches or match the at least onespace as represented by the obtained one or more pieces of calendarinformation; and in case such a match is found: determine one or morereference location estimates, wherein a respective reference locationestimate of the one or more reference location estimates is indicativeof a location of the space that was determined to be a match, whereinthe location of the space is derived from the indoor map.
 15. Theapparatus according to claim 14, wherein the calendar information isfurther indicative of a time period of the at least one appointment, andwherein the at least one memory and the computer program code areconfigured to, with the at least one processor, cause the apparatusdetermine of the one or more coarse location estimates by: obtaining orgathering one or more pieces of fingerprint information, wherein theobtaining or the gathering is performed and/or controlled during thetime period of the at least one appointment; and wherein the one or morecoarse location estimates are determined at least partially based on theone or more pieces of fingerprint information.
 16. The apparatusaccording to claim 15, wherein the set of space identifiers is extractedfurther based on the one or more coarse location estimates, and whereinthe set of space identifiers comprises one or more spaces located in thevicinity of the one or more coarse location estimates.
 17. The apparatusaccording to claim 15, wherein the at least one memory and the computerprogram code are further configured to, with the at least one processor,cause the apparatus to: determine one or more outliers of the determinedone or more reference location estimates at least partially based on acomparison of one or more pieces of fingerprint information obtainedfrom one or more further mobile devices with the one or more pieces offingerprint information gathered or obtained; and discard such one ormore pieces of fingerprint information of the one or more pieces offingerprint information gathered or obtained in case a mismatch ofpieces of fingerprint information is determined by the comparison.
 18. Atangible computer-readable medium storing computer program code, thecomputer program code when executed by a processor causing an apparatusto perform and/or control: obtain one or more pieces of calendarinformation indicative of at least one appointment taking place in aspace; extract a set of space identifiers representing one or morespaces of the venue, wherein the one or more spaces respectively theirone or more space identifiers are extracted based on an indoor map ofthe venue; determine or trigger determining whether at least a part ofthe set of space identifiers or one or more spaces of the set of spaceidentifiers matches or match the at least one space as represented bythe obtained one or more pieces of calendar information; and in casesuch a match is found: determine one or more reference locationestimates, wherein a respective reference location estimate of the oneor more reference location estimates is indicative of a location of thespace that was determined to be a match, wherein the location of thespace is derived from the indoor map.
 19. The tangible computer-readablemedium according to claim 18, wherein the calendar information isfurther indicative of a time period of the at least one appointment, andwherein the computer program code when executed by the processor causingthe apparatus to determine of the one or more coarse location estimatesby: obtaining or gathering one or more pieces of fingerprintinformation, wherein the obtaining or the gathering is performed and/orcontrolled during the time period of the at least one appointment; andwherein the one or more coarse location estimates are determined atleast partially based on the one or more pieces of fingerprintinformation.
 20. The tangible computer-readable medium according toclaim 19, wherein the computer program code when executed by theprocessor further causing the apparatus to: determine one or moreoutliers of the determined one or more reference location estimates atleast partially based on a comparison of one or more pieces offingerprint information obtained from one or more further mobile deviceswith the one or more pieces of fingerprint information gathered orobtained; and discard such one or more pieces of fingerprint informationof the one or more pieces of fingerprint information gathered orobtained in case a mismatch of pieces of fingerprint information isdetermined by the comparison.